Local Calling Guide

Area code/prefix search

Search area code/prefix (NPA/NXX)
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NPA: 203 [Rate centres in NPA 203] [Dial plan for NPA 203]

NXX: 557

NPA-NXX BLOCK Rate Centre Region Switch OCN LATA LIR Eff date Disc date
203-557 A Westport CT NRWLCT02YMD  4950 CABLEVISION LIGHTPATH, INC. - CT 920      
203-557 0 Westport CT   612K CSC VOICE, LLC 920      
203-557 1 Westport CT NRWLCTCVDS0  4950 CABLEVISION LIGHTPATH, INC. - CT 920      
203-557 2 Westport CT NRWLCTCVDS0  4950 CABLEVISION LIGHTPATH, INC. - CT 920      
203-557 3 Westport CT   612K CSC VOICE, LLC 920      
203-557 4 Westport CT   612K CSC VOICE, LLC 920      
203-557 5 Westport CT NRWLCTCVDS0  4950 CABLEVISION LIGHTPATH, INC. - CT 920      
203-557 6 Westport CT   612K CSC VOICE, LLC 920   2015-07-25   
203-557 7 Westport CT NRWLCTCVDS0  4950 CABLEVISION LIGHTPATH, INC. - CT 920      
203-557 8 Westport CT   612K CSC VOICE, LLC 920      
203-557 9 Westport CT NRWLCTCVDS0  4950 CABLEVISION LIGHTPATH, INC. - CT 920      

Last updated: Thu, 16 Oct 2025 03:04:18 UTC

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